python/v1.57.1

python/v1.57.1

Auto-drafted from commits in python/v1.57.0..python/v1.57.1, grouped by conventional-commit type. Edit on the release page after publish if you want a polished writeup; the canonical release notes live on the website.

🚀 Features

• feat(bidi): add snapshot capture and restore (#4584) (b8a2e5c)
• feat(cli): replace setup Q&A with Quickstart, Customize, and Export, and add /tools (#4581) (9b7657f)
• feat(py): add a2a_client vended tool (#4304) (9746df6)
• feat(mcp-ts)!: swap to @modelcontextprotocol/client 2.0 (#4093) (ab8ff46)
• feat(bidi): require explicit model IDs for providers (#4525) (8732c7c)
• feat(agent): add Agent.shutdown() for scope-based cleanup (#4519) (fec0427)

🐛 Fixes

• fix(py): update model id in cancellation integ tests (#4611) (6da3f48)
• fix(session): rewrite all stored copies of a message when guardrail redacts it (#4606) (69a465e)
• fix(bidi): record tool dispatch in conversation history (#4605) (4dc582c)
• fix(bidi): align response boundaries and transcript history (#4560) (09e2fe3)
• fix(graph): finalize invocation before yielding the result (#4580) (3d4cf9a)
• fix(python): cap sqlalchemy<2.1.0 to avoid RecursionError in Hatch dependency check (#4583) (711be5d)
• fix(a2a): extract content from task.status.message when artifacts are absent (#4511) (7f2b0c5)
• fix(mcp-server): migrate off removed mcp.server.fastmcp for mcp 2.x compat (#4547) (18becd7)
• fix: simplify and clarify CLI UX; fix bugs (#4548) (43b15b7)
• fix(hitl): reject non-boolean classifier decisions (#4538) (08f5bdd)
• fix(site): render search overlay correctly on standalone pages (#4529) (3cff1be)
• fix(cli): align @strands-agents/sdk range with harness (fixes interventions instanceof crash) (#4530) (d13c214)
• fix(cli): improve onboarding and terminal responsiveness (#4518) (2db4074)

♻️ Refactoring

• refactor(bidi): remove response stop reasons (#4604) (b5dac92)
• refactor(bidi): use barge-in terminology (#4566) (e83c048)

📚 Documentation

• docs(site): add PyBay and Open Source Summit Europe to events (#4562) (0411de6)
• docs(harness): add versioning policy for Strands harness and the CLI (#4535) (2c49c9c)
• docs: add authorship to Strands harness (#4521) (adb9c24)
• docs(changelog): sync strands-agents/harness-sdk python/v1.57.0 (#4517) (880c5bd)
• docs(changelog): sync strands-agents/harness-sdk typescript/v1.19.0 (#4516) (68cf9d2)

👷 CI

• ci: add Python lint/format gate to pre-commit hook (#4528) (219dbf6)
• ci(python): enforce formatting checks (#4526) (83a7f47)

🔧 Chores

• chore(cli): depend on harness ~0.1.1 (#4582) (7ae759d)
• chore(harness-ts): lift the @strands-agents/sdk <1.18.0 cap (#4520) (15c42ff)